In the past, transformers have suffered from harmonic distortion, poor frequency response, and high impedance especially at low frequencies. Previously, this has necessitated the transformer to be physically large. In order to overcome these and other drawbacks of the prior art, the present invention allows a transformer to be smaller and have a much better performance. In particular, the present invention makes use of a high impedance feedback network to generally improve performance while retaining all the advantages of the transformer. More specifically, the present invention includes a secondary high impedance differential negative feedback circuit which is employed from the transformer secondary to the amplifiers. This reduces distortion, improves frequency response, eliminates ringing, lowers output impedance and due to the differential nature of the circuit, greatly improves longitudinal balance. Overall stability and phase response are also improved.